Starter/Generator
The mild hybrid's one electric machine: a belt-driven unit that replaces the alternator and handles most engine restarts, typically at forty-eight volts. Because one machine does both jobs, one fault takes out charging and restarting together — and the first symptom most owners notice is the quietest one, stop-start silently refusing to operate while the car otherwise drives normally. The belt matters more than intuition suggests: a slipping belt makes the machine underperform in ways its control module reports as its own trouble.
Also known as: bsg, belt starter generator, isg, integrated starter generator, mild hybrid motor, 48v starter generator, bisg
Referenced by 6 codes
Codes involving this component (6)
- P06EF Engine Restart Performance Moderate
- P0A1E Starter/Generator Control Module Moderate
- P2BA3 Starter/Generator Mechanical Performance Moderate
- U0120 Lost Communication With Starter/Generator Control Module Moderate
- U0469 Invalid Data Received From Starter/Generator Control Module Moderate
- U3003 Battery Voltage Moderate
Other components in Hybrid Propulsion
- High Voltage Battery 795
- Power Inverter 370
- Motor Generator 249
- Hybrid/EV Battery Pack Sensor Module 243
- Battery Energy Control Module 228
- On-Board Charger 209
- Hybrid Battery Contactor 136
- Charge Port 131
- DC-DC Converter 99
- Inverter Coolant Pump 92
- Motor Current Sensor 73
- Electric A/C Compressor 63
- Inverter Coolant Temperature Sensor 60
- Motor Position Sensor 59
- Hybrid Battery Cooling Fan 54
- Battery Pack Coolant Control Valve 47
- Hybrid/EV Battery Pack Current Sensor 30
- Hybrid Powertrain Control Module 19
- Motor Temperature Sensor 18
- High Voltage Interlock Loop 15
- Drive Motor Control Module 15
- Active Engine Mount 6
- High Voltage Service Disconnect 5
- Fuel Cell Stack 2
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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